CN100471366C

CN100471366C - Separator plate for the production of circuit board components

Info

Publication number: CN100471366C
Application number: CNB2003801073419A
Authority: CN
Inventors: 额恩斯特-迪耶特·巴克豪斯
Original assignee: C2C Technologie fuer Leiterplatten GmbH
Current assignee: AT&S China Co Ltd
Priority date: 2002-12-27
Filing date: 2003-12-29
Publication date: 2009-03-18
Anticipated expiration: 2023-12-29
Also published as: CN1732725A; ATE332626T1; ATA19372002A; KR101118696B1; US7097915B2; EP1576864B1; TW200418353A; US20040151941A1; AU2003287760A1; AT411893B; KR20050089990A; WO2004060036A1; EP1576864A1; DE50304175D1

Abstract

Disclosed is a separator plate (3) for producing printed circuit board components by pressing individual layers. Said separator plate comprises a metallic core layer (3.1) and a coating on at least one face of the core layer. The coating on the core layer (3.1) is applied to the core layer by cold plating and is made of a metal that is provided with a greater surface hardness than the metallic core layer (3.1) while the metallic core layer (3.1) is made of a metal that conducts heat well compared with the outer metal layer (3.2).

Description

Be used to produce the dividing plate of printed circuit board component

Technical field

The present invention relates to be used for produce by compressed single the dividing plate of printed circuit board component, this dividing plate has metal core layer and this core layer coating on the one side at least.

Background technology

Known, in order to produce the printed circuit board component that constitutes by a plurality of layers, especially in order to produce so-called multilayer board or to be called for short multilayer, single-layer compressed bag (Einzellagenpresspaket) is for example interconnecting about 180 ℃ the time in corresponding layering compacting or the vacuum pressing.Each structure comprises produces the necessary Copper Foil of printed circuit cable, also comprises synthetic resin layer (prepreg layer is generally epoxy resin layer) or laminate layers.Can imagine the production that can compare with multilayer circuit board production at the so-called basic material (Basismaterial) that is used for printed circuit board (PCB), basic material is usually directed to the synthetic resin layer (prepreg layer) of one side or dual coating conductive layer (especially Copper Foil).These basic materials also are used as so-called " internal layer " when producing multilayer circuit board, and also form printed circuit board component.

Usually, when above-mentioned compacting, a plurality of compactings wrap in and are overlapped the to each other structure in the forming press, and these bags are also referred to as pressure strip by dividing plate, separation mutually.Dividing plate at first has such function, promptly produces uniform pressure and temperature and distribute when compressed single, so that obtain the measured printed circuit panel products of matter.Dividing plate comprises steel plate or aluminium sheet mostly, and therefore is also referred to as partition.Based on described function, they should be harder than Copper Foil.If consider that printed circuit cable is more and more thinner in modern printed circuit board (PCB), and its spacing is also more and more littler, then this structure highly significant.For example, in so-called high-tech printed circuit board (PCB), according to the HDI technology (the HDI-high density interconnect: High Density Interconnect-technology), used thickness＜12 μ m, for example Copper Foil of 5 μ m only.Such danger is wherein arranged, and promptly printed circuit cable may squeeze the surperficial Copper Foil of wearing in the compacting bag when compacting, and this effect is called as " image transfer (Imagetransfer) ".Therefore, in order to avoid this image transfer in the mode of economy, in multilayer technique, use mostly thickness for example as the special steel plate of 1.5mm or 1.2mm as dividing plate, because these special steel plates have high case hardness, in addition, also as desirable, can be repeated to use for economic reasons.

But, on the other hand, comparatively speaking, special steel is relatively poor heat conductor, wherein, in above-mentioned HDI printed circuit board (PCB) with more and more littler printed circuit cable width and spacing, in order to guarantee corresponding quality, quick especially and uniform heat distribution is important on each laminar surface and on whole height of the heap that will suppress (Stapel) or the thickness.Therefore, the known dividing plate with better thermal conductivity is especially by aluminium (perhaps aluminium alloy; If hereinafter mention aluminium, then also represent aluminium alloy) constitute, referring to US 5 153 050 A.But, to compare with the special steel dividing plate, aluminium flake has low-down case hardness as dividing plate, and it has only the yield point that for example is approximately special steel yield point 40%.For this reason, aluminium is in press temperature, at about 180 ℃ to 200 ℃, loses the about 25% of its intensity (yield point), and by " softening annealing ".Also caused above-mentioned image transfer thus.In contrast, when the press temperature of 180 ℃ or 200 ℃, in the special steel dividing plate, in fact intensity or case hardness also do not change.

Another shortcoming of aluminium dividing plate is, compares with other suitable metals of great majority, and aluminium has high thermal coefficient of expansion.Therefore, as mentioned above, when compacting, particularly after epoxy resin liquefaction,, produce the skew of each layer that will suppress in the compacting bag (Presspaket) so if the aluminium dividing plate expands, and particularly in the lead group width in the micrometer range of mentioning, or rather 100 μ m for example with and under width in, this may cause infringement, and therefore causes waste product.

The above-mentioned shortcoming relevant with the aluminium dividing plate is effective equally for the dividing plate of producing with copper.Therefore copper is good heat conductor, and has guaranteed quick and uniform heat distribution in the compacting heap, and still, copper can not satisfy for fear of image transfer above-mentioned and to the standard of intensity or case hardness.

In addition, the dividing plate of producing with aluminium is for example also disclosed, wherein in US 5 256 474 A, in this dividing plate, on the aluminium core layer, the anti-adhesion layer (Antihaftschicht) of coating on two sides is so that can separate with the copper layer of printed circuit board (PCB) at an easy rate at the compacting rear bulkhead.But, the aluminium flake dividing plate that also relates to have the top shortcoming of being mentioned here.

On the other hand, WO 99/53737 A and WO 02/058448 A disclose the dividing plate with the substrate that is made of steel alloy, according to WO 99/53737 A, and at least one copper layer of coating on substrate; But this copper layer as described have low case hardness like that, and core layer, promptly substrate has low thermal conductivity; This shortcoming also exists in according to the dividing plate of WO 02/058448 A, and metal sandwich wherein is set there, the metal sandwich that is made of aluminium especially, its continuous surface metal-layer, especially surface metal-layer and the base steel sheet that is made of copper; These surface metal-layers, especially copper layer are embedded in the electric component that will produce, are not the part of real dividing plate strictly speaking therefore.

Summary of the invention

Task of the present invention provides a kind of dividing plate of being mentioned when this paper begins, by means of this dividing plate can with satisfactory way satisfy above-mentioned, because the material behavior that is associated and conflicting, relate in one aspect to that uniform heat distributes and the requirement that relates to high strength or case hardness on the other hand.Wherein, the present invention is based on such consideration, promptly baffle plate configuration is a composite separator, and therefore provides and use the characteristic of different metal in combination.

Therefore, in dividing plate according to the present invention, existence is by the high-termal conductivity metal, for example aluminium or copper, the core layer of formation or intermediate layer, and this core layer is at least on a side, be preferably on two sides, by cold plating (Kaltplattieren) or roll to electroplate (Walzplattieren) and with hard metal, for example special steel, carbon steel, but also can be nickel etc., link to each other.Wherein, this hard metal plating can be thinner, the about thickness of the 0.075mm order of magnitude for example, on the contrary, and core, for example the core that is made of aluminium or copper has for example thickness of 0.35mm.In roll plating or cold plating, realize that with fusing mode metallic surface connects, also obtain favourable effect thus, promptly when heating, only may produce thermal expansion, if i.e. heat-conducting metal, for example aluminium or copper corresponding to that of hard metal plating, only be used for dividing plate, so no longer produce the great thermal expansion of these metals.Therefore, originally just worked when the high relatively temperature, but this high temperature does not occur when producing printed circuit board (PCB) at each layer of concrete compacting than the thermal expansion of the little a lot of for example steel of the thermal expansion of aluminium.For example, size is the aluminium dividing plate of 600 * 450mm obtains about 5mm on each direction expansion, the dividing plate of this size that constitutes by steel-but only when high temperature-have only the expansion of about 2mm, but only when higher temperature, on the contrary, when 180 ℃ of temperature that the time relates in compacting or 200 ℃, has only 0.1mm-0.2mm.Because with hard plated material welding, so the core layer that is made of heat-conducting metal also must adapt to this little expansion phase.

Another advantage according to dividing plate of the present invention is, although be produced as composite plate, but also can obtain low cost, this is because aluminium has low relatively proportion, makes the purchasing price of calculating by kilogram of aluminium relatively littlely be reflected in the dividing plate sale price of calculating by the dividing plate area.

Therefore, in sum, obtained a kind of dividing plate by the present invention, on the one hand, itself since the good thermal conductivity of the core that thermal conductivity is played a decisive role (for the gross mass of dividing plate, about 75% is Heat Conduction Material, aluminium for example, and has only 25% hard metal, steel for example), so surface and stack height (Stapelhoehe) are gone up uniform heat distribution when having guaranteed compacting, promptly when using according to dividing plate of the present invention, epoxy resin in fact once just all becomes liquid state, and on the other hand, it has essential case hardness by the hard metal of electroplating, so that avoid undesirable image transfer, and so that also makes dividing plate to be used multiple times in pressing process.Wherein,, also advantageously may on the hard metal level on surface, apply lubricant, for example based on the lubricant of olefine in order to suppress.

Description of drawings

Below will be by means of represented in the accompanying drawing, particularly preferred embodiment further sets forth the present invention, but the present invention is not limited to this.Wherein:

Fig. 1 represents to have the structure of the multilayer compacting bag of a plurality of individual layers and dividing plate composite component with schematic diagram;

Fig. 2 exemplarily represents to have the dividing plate composite component of barrier film capsule (Trennfoliensack);

Fig. 3 represents the exemplary top view according to the dividing plate composite component of Fig. 2; And

Fig. 4 represents the exemplary cross section of dividing plate, and it can be used in the structure of Fig. 1 to 3, and it is a purpose of the present invention.

Embodiment

In Fig. 1, exemplary and partly represented multilayer compacting bag, wherein represented, dividing plate composite component 1 be used for single layer structure 2 multilayer board, that the back abbreviates structure 2 as alternately.The dividing plate composite component 1 that dashed rectangle is represented comprises dividing plate 3, is also referred to as pressure strip, partition or clamping piece, is equipped with the Copper Foil 5 of resin bed 4 on it here for coating above the anti-adhesion layer 6 of iris-diaphragm.The integral body of the Copper Foil 5 that has the

Copper Foil

5,4, barrier film 6, partition 3, another barrier film 6 of resin coating and apply with synthetic resin 4 is combined into composite component 1 in advance, below will elaborate in an embodiment by means of Fig. 2 and 3.

The Copper Foil that is coated with resin 54 of composite component 1 is the composition of multilayer board, and in addition, the etched internal layer 7 (basic material) and the synthetic resin layer (prepreg layer) 8 of structure 2 also belong to multilayer circuit board.

Such dividing plate composite component 1 can be set to the unit and when producing circuit board (element) can with the alternately overlapped accumulation of multilayer-individual layer, simplified the accumulation in the compacting thus widely, this is because five elements 4/5 can once be set in a process; 6; 3; 6; 5/4.This has reduced the processing time (Handlingzeit) greatly.Etched internal layer 7 is realized the circuit or the conductor model of hope, and by means of prepreg layer 8 that they are bonding mutually.This is connected in the compacting when the temperature that improves (for example at 180 ℃ time) and realize in pressure or vacuum.Shown in Fig. 1 part is exemplary, in such compacting bag, can overlap the to each other 20 structures 2 of coating.Between each structure 2, dividing plate composite component 1 is set, wherein level and smooth, the neat surface of the partition 3 responsible multilayer boards of being produced.

In the compacting cycle period that is limited, the synthetic resin of prepreg layer 8 begins to flow.Prevent that by being provided with adhesion layer or interlayer 6 prevent that the resin of layer 8 from arriving partition or general dividing plate 3, and prevented that resin from flowing to the edge of dividing plate 3.

According to Fig. 2 and 3, barrier film separately is set as anti-adhesion layer 6, and these barrier films 6 are bigger than dividing plate 3, and bigger than the Copper Foil 5 that has resin bed 4.As shown in Figure 2, in this case, Copper Foil 5 is preferably identical size with dividing plate 3, even Copper Foil 5 may be very fine less than dividing plate 3.Because dividing plate 3 is all stretched out in barrier film 6 each sides, so can catch mobile resin.In order to make resin can not arrive dividing plate 3 between barrier film 6, barrier film 6 interconnects by means of pressure-sensitive adhesive, acrylic acid adhesive or fusing adhesive (Schmelzkleber) along cemented side seam 9.Thus, dividing plate 3 is closed between the interconnective barrier film 6 of cryptomere, and promptly dividing plate 3 is in the barrier film capsule, and its median septum is provided with versatilely by freedom in this barrier film capsule.

On the other hand, Copper Foil 5 for example melts adhesive also by means of adhesive, and especially hot melt adhesive or acrylic acid adhesive stick on the barrier film 6 with the form of cemented side seam 10.

Fig. 4 represents that dividing plate 3 has special, novel composite construction in order better to show exemplary cross section (not having hacures), dividing plate 3.Particularly, setting is by the high-termal conductivity metal, for example aluminium or copper, the interlayer or the core layer 3.1 that constitute, and this core layer 3.1 electroplates by rolling outwardly at two faces, is generally cold plating, link to each other with the metal level 3.2 of outside, metal level constitutes by comparing hard metal with core layer 3.1, and for example by special steel, carbon steel, perhaps metal such as nickel constitutes.When being coated in the hard metal level 3.2 on these surfaces on the core layer 3.1 by cold plating, cause the welding of two kinds of metals, produce stable, plane thus and connect.In the dividing plate of finishing 3, this stable plane connects and has caused, no longer can expand when relatively the metal level 3.2 of surface (promptly with respect to) core layer that metal constituted 3.1 that heat conduction is good is heated, promptly produced thermal expansion corresponding to those surface metal-layers 3.2 that constitute by hard metal with degree such under the situation about freely existing with them.

In an example, dividing plate 3 comprises that thickness is approximately core layer 3.1 0.35mm, that be made of aluminium, and the core layer two sides is provided with thickness and is about surface metal-layer 0.075mm, that be made of special steel.Obtained combination thermal conductivity thus, but this combination thermal conductivity promptly is approximately 170W/m.K with respect to 210W/m.K but in the order of magnitude of the thermal conductivity of aluminium less than independent aluminium (or aluminium alloy).On the other hand, the combined thermal expansion of this composite diaphragm 3 corresponds essentially to the thermal expansion of steel, especially special steel or carbon steel, promptly for example be aluminium thermal expansion 1/25 to 1/50.

Another object lesson that stands the test in reality test has following structure during for 0.5mm in the dividing plate gross thickness:

0.05mm special steel (or steel)

0.40mm aluminium

0.05mm special steel (or steel)

Thus, obtain following physical values, the meaning of this composite diaphragm be described by means of these physical values:

	Aluminium	Special steel	Composite material (dividing plate)
	Aluminium	Special steel	Composite material (dividing plate)	Intensity/case hardness (Mpa)	About 240	About 800	About 800

Thermal conductivity (W/m.K)	210	25	170
Thermal conductivity (W/m.K)	210	25	170	Thermal expansion (10 ^-6.K ^-1)	23.5	10.5	10.5

As shown in Figure 4, two faces that composite diaphragm 3 can also the surface are provided with surface lubricant layer 3.3, and wherein this lubricant layer can be set up on the olefine basis in known manner.

This composite diaphragm 3 that comprises different metal can be used for the described dividing plate composite component as Fig. 1 to 3, but it can certainly for example according to US 5 356 474 A, use in the compacting bag in the known independent structure in the same manner in the prior art.Especially, this composite diaphragm 3 has brought such advantage, the i.e. combination of conflicting effect own, i.e. on the one hand high strength and case hardness and good on the other hand thermal conductivity, so that compressed single guarantee when producing printed circuit board component epoxy resin fast, liquefaction uniformly, and prevent from image transfer or damaged surfaces from also to guarantee the repeated use of dividing plate 3.

Claims

1. dividing plate (3) that is used for by a plurality of individual layers are suppressed to produce printed circuit board component, described dividing plate (3) comprise metal core layer (3.1) with by compare the coating that metal with high surface hardness constitutes with described metal core layer (3.1), it is characterized in that, coating on two faces of described core layer (3.1) is made of the surface metal-layer (3.2) that is coated in by cold plating on the described core layer, and wherein said metal core layer (3.1) constitutes by compare the good metal of heat conduction with described two surface metal-layers (3.2).

2. according to the dividing plate of claim 1, it is characterized in that described surface metal-layer (3.2) is electroplated coating by rolling.

3. according to the dividing plate of claim 1 or 2, it is characterized in that described surface metal-layer (3.2) is made of steel.

4. according to the dividing plate of claim 3, it is characterized in that described surface metal-layer (3.2) is made of special steel.

5. according to the dividing plate of claim 3, it is characterized in that described surface metal-layer (3.2) is made of carbon steel.

6. according to the dividing plate of claim 1 or 2, it is characterized in that described surface metal-layer (3.2) is made of nickel.

7. according to the dividing plate of claim 1 or 2, it is characterized in that described core layer (3.1) is made of aluminium.

8. according to the dividing plate of claim 1 or 2, it is characterized in that described core layer (3.1) is made of copper.

9. according to the dividing plate of claim 1 or 2, it is characterized in that described core layer (3.1) thickness is 0.35mm.

10. according to the dividing plate of claim 1 or 2, it is characterized in that described surface metal-layer (3.2) thickness is 0.075mm.

11. the dividing plate according to claim 1 or 2 is characterized in that, goes up coating lubricant (3.3) at described surface metal-layer (3.2).

12. the dividing plate according to claim 11 is characterized in that, described lubricant (3.3) is based on olefine.